xref: /openbmc/linux/arch/arm/include/asm/arch_timer.h (revision 2f828fb2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASMARM_ARCH_TIMER_H
3 #define __ASMARM_ARCH_TIMER_H
4 
5 #include <asm/barrier.h>
6 #include <asm/errno.h>
7 #include <linux/clocksource.h>
8 #include <linux/init.h>
9 #include <linux/types.h>
10 
11 #include <clocksource/arm_arch_timer.h>
12 
13 #ifdef CONFIG_ARM_ARCH_TIMER
14 int arch_timer_arch_init(void);
15 
16 /*
17  * These register accessors are marked inline so the compiler can
18  * nicely work out which register we want, and chuck away the rest of
19  * the code. At least it does so with a recent GCC (4.6.3).
20  */
21 static __always_inline
22 void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
23 {
24 	if (access == ARCH_TIMER_PHYS_ACCESS) {
25 		switch (reg) {
26 		case ARCH_TIMER_REG_CTRL:
27 			asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
28 			break;
29 		case ARCH_TIMER_REG_TVAL:
30 			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
31 			break;
32 		}
33 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
34 		switch (reg) {
35 		case ARCH_TIMER_REG_CTRL:
36 			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
37 			break;
38 		case ARCH_TIMER_REG_TVAL:
39 			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
40 			break;
41 		}
42 	}
43 
44 	isb();
45 }
46 
47 static __always_inline
48 u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
49 {
50 	u32 val = 0;
51 
52 	if (access == ARCH_TIMER_PHYS_ACCESS) {
53 		switch (reg) {
54 		case ARCH_TIMER_REG_CTRL:
55 			asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
56 			break;
57 		case ARCH_TIMER_REG_TVAL:
58 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
59 			break;
60 		}
61 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
62 		switch (reg) {
63 		case ARCH_TIMER_REG_CTRL:
64 			asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
65 			break;
66 		case ARCH_TIMER_REG_TVAL:
67 			asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
68 			break;
69 		}
70 	}
71 
72 	return val;
73 }
74 
75 static inline u32 arch_timer_get_cntfrq(void)
76 {
77 	u32 val;
78 	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
79 	return val;
80 }
81 
82 static inline u64 arch_counter_get_cntpct(void)
83 {
84 	u64 cval;
85 
86 	isb();
87 	asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
88 	return cval;
89 }
90 
91 static inline u64 arch_counter_get_cntvct(void)
92 {
93 	u64 cval;
94 
95 	isb();
96 	asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
97 	return cval;
98 }
99 
100 static inline u32 arch_timer_get_cntkctl(void)
101 {
102 	u32 cntkctl;
103 	asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
104 	return cntkctl;
105 }
106 
107 static inline void arch_timer_set_cntkctl(u32 cntkctl)
108 {
109 	asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
110 	isb();
111 }
112 
113 #endif
114 
115 #endif
116